Heat exchanger



Patented Apr. 6, 1943 Addison Y. Gunter, Larchmont, N. Y., assignor to American Locomotive Company, New York, N. Y., a corporation of New York Application April 9, 1942, Serial No. 438,260

1 Claim.

This invention-relates to heat exchangers.

' An object of the invention is to provide a simplified heat exchangerin which the exchange is accomplished between two fluids having series flow in two or more passes.

,Other and further objects of this invention will appear from the following description, the accompanying drawing and the appended claim.

' Referring to the drawing forming a part of this application, Figure 1 is a view of a heat exchanger embodying the present invention, shown partly in side elevation and partly in section on the line 1-1 of Fig. 2, parts being shown in full and parts being broken away, the heat exchanger being foreshortened; Fig. 2 is an end View of the exchanger as viewed from the right of Fig. 1; Fig. 3 is an end view of the exchanger as viewed from theleft of Fig. 1, parts being broken away;

and Fig. 4 is a foreshortened view of the ex changer, shown partly in plan and partly in section on the line IV-IV of Fig. 2, parts being shown in full.

The heat exchanger, indicated generally by the reference numeral l, includes a shell 2 closed at its forward end by a header 3 and at its rear end by a header 4. Shell 2 is a hollow cylinder of plate metal. The exchanger is shown in Fig. 1 ina horizontal position and it will be so described, it being understood that it may be disposed in other positions if desired.

Header 3 is shown as a built-up structure and includes a tube sheet 5 which fits in the forward end of shell 2 and is welded thereto, as clearly designated in Fig. 1 by the reference numeral 6. The tube sheet 5 has an upper opening I and lower opening 8, vertically aligned in the vertical center plane of the exchanger.

Header 4 is shown made of two castings secured together and includes a tube sheet 9 secured to the rear end of the shell. In the present instance the tube sheet 9 includes a cylindrical flange which is butt-welded to the end of the shell, as clearly shown in Fig. 1, the weld being designated by the reference numeral H. Tube sheet 9 has openings l2 and L3 in line respectively with open ings I and 8. r

The exchanger further includes cylindrical sleeves [4 which are disposed with their rear ends in openings l2 and I3. Each sleeve l4 extends forwardly from tube sheet 9 through shell 2, the upper one passing through opening 1 and the lower one through opening 8 and forwardly of the tube sheet a predetermined distance, the portions forward of the tube sheet 5 forming part of the header 3. These portions may be separate from the portions in the shell, if desired. Sleeves l4 preferably have a sliding fit in openings l2 and I3 and are expanded in openings 1 and 8, a tongue and groove connection 15 being provided to prevent escape of shell fluid through openings 1 and 8. The sliding fit in openings l2 and 13 allows free expansion and contraction of sleeves l4. The forward end of each sleeve I4 is threaded.

A pipe fitting I6 is connected to the side wall of each sleeve 14 forward of tube sheet 5, each pipe fitting opening into its sleeve. It is contemplated that the top fitting IS in Fig. 1 will form the inlet to the exchanger for shell fluid and the bottom fitting I6 will form-the outlet. The fittings are vertically aligned and oppositely directed. The portions of sleeves l4 forward of tube sheet 5 form header chambers, the top portion an inlet and the bottom portion an outlet chamber.

Tube sheet 9 further includes two openings l1 and I8 (see Fig. 4) horizontally aligned on the horizontal center plane of the exchanger, openings l, 3, l2, I3, I! and I8 preferably all being.

of the same size. The exchanger further includes sleeves l9 which are disposed with their rear ends'expanded into openings I1 and .I8, tongue and groove connections 20 being provided to prevent displacement of sleeves 19 from their openings IT and I8. Sleeves l9 extend forwardly from tube sheet 9 but stop well short of tube sheet 5, opening at their forward ends directly into shell 2. They are thereby free to expand and contract.

Header 4 further includes a hollow cover 2| divided by a diagonal wall 22 into two compartments 23 and 24. Compartment 23 affords communication between the upper sleeve 14 and one sleeve l9, and compartment 24 afiords communication between the lower sleeve l4 and the other sleeve I9.

a fluid-tight connection.

Tube sheet 5 further includes two orifices 21, one in line with each of the openings I1 and H! but of smaller diameter.

Tube sheet 9 and cover 2| are secured? together by stud bolts 25, a gasket 26 providing? forwardly from each U-bend 30 through the sleeves l9, these legs extending at their forward ends through the orifices 21, and being threaded at their forward ends. In each orifice 21 is a flanged coupling 3| surrounding and secured to the adjacent leg, the flange engaging the inner face of tube sheet 5. Couplings 3! are threaded exterior or the shell, and nuts 32 secured thereon hold the flange in fluid-tight engagement with the tube sheet 5. The legs of the U-tube, being secured only at their forward ends, are free to expand and contract, the U-bends 30 floating each in its compartment.

A U-bend 33 connects the forward ends of the legs in sleeves I 9, unions 34 forming the connections.

Flanged couplings 35 surround and are secured to the forward ends of the legs in sleeves M by tongue and groove expanded connections 36. An orificed cap 31 is screwed on the threaded end of each sleeve l t, a coupling 35 extending through each cap orifice and being threaded at its forward .end. A nut 38 is threaded on the coupling in engagement with the cap 31, the'nut and cap closingthe forward end of the sleeve 64, and the coupling flange engaging the inner face of the cap.

lhe U-bend tube may be removed from the exchanger through the rear end by first removing the cover 2|, the unions 34 and the nuts 32 and '38, the flanges of the couplings 3i and 35 being of smaller diameter than the inside diameter of the sleeves to permit withdrawal of the couplings through the sleeves.

The inlet end of tube 28 is designated by the reference numeral 39. Thus the tube fluid makes four series passes in the exchanger before reaching the outlet, indicated by the reference numeral 40. Similarly the shell fluid makes four series passes, entering the upper fitting l6, passing through the upper sleeve i4 into compartment 23 and therefrom through the correlated sleeve l9 into shell 2, therefrom through the other sleeve l9 into compartment 24 and therefrom through the lower sleeve l4 and out through the lower fitting I6.

' It will be understood'from the foregoing description that the heat exchanger of the present invention presents a simple construction free from damage due to expansion and contraction of parts and permitting heat exchange by series flow through four passes of fluid. However it is contemplated that the heat exchange may be accomplished with a greater or lesser number of passes.

While these has been hereinbefore described an approved embodiment of this invention, it will be understood that many and various changes and modifications in form, arrangement of parts and details of construction anayibe made thereto without departing from the spirit of the invention, and that all such changes and modifications as fall within the scope of the appended claim are contemplated as a part of this invention.

The invention claimed and desired to be secured by Letters Patent is:

A heat exchanger for heat transfer between two fluids, comprising a shell; a header at one end thereof; a tube sheet at the other end thereof; two short and two long sleeves extending longitudinally in said shell, said header having a header plate and a detachable cover for said plate having two compartments, said sleeves, at one end thereof, extending into orifices formed in said plate, a long and a short sleeve thereby communicating with each compartment, said short sleeves opening at their other ends into said shell, said long sleeves extending through said tube sheet and having end portions therebeyond; closures for said end portions, said end portions each having an orifice providing one an inlet and the other an outlet, said sleeves, compartments and shell cooperating through intercommunication thereof for series flow therethrough of one of said fluids, said short sleeves being secured in said plate and said long sleeves slidably engaging said plate and being secured in said tube sheet, whereby said sleeves are free for expansion and contraction; and a fin tube having U-bends disposed one in each of said compartments and legs extending through said sleeves from the ends of each U- bend, the legs extending through said short sleeves further extending through said tube sheet and having end portions extending therebeyond said tube further having a U-benddisposed exterior of said shell connecting said tube end portions, the legs extending through said long sleeves extending through said closures thereof,

one providing an inlet and the other an outlet for said other fluid, said legs and U-bends cooperating through inte-rcomrnunication thereof for series flow therethrough of said other fiuid. ADDISON Y. GUN'IER. 

